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Finding the Fourth Proportional to 688.10, 965.50 and 688.10

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Solution

The fourth proportional to 688.10, 965.50 and 688.10 is: 965.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    688.10 : 965.50 = 688.10 : x
  2. Step 2: Convert to fraction form
    688.10/965.50 = 688.10/x
  3. Step 3: Cross multiply
    688.10x = 965.50 × 688.10
  4. Step 4: Simplify right side
    688.10x = 664,360.55
  5. Step 5: Solve for x
    x = 664,360.55/688.10
  6. Step 6: Final answer
    x = 965.50

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.40) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.